Continuous fiber/polymer composites have been employed in a wide variety of applications. For example, continuous fiber composites have been used to form fiber reinforced composite tapes, ribbons, rods and profiles useful as lightweight structural reinforcements as well as protective casings. Continuous fiber composites have also been utilized in melt processing techniques such as injection molding for formation of products exhibiting high strength characteristics in a variety of desirable applications.
A significant problem with continuous fiber composites is that they often rely upon thermoset resins (e.g., vinyl esters) to help achieve the desired strength properties. Thermoset resins are difficult to use during manufacturing and do not possess good bonding characteristics for forming composites with other materials. In response, attempts have been made to form continuous fiber composites with thermoplastic resins. Unfortunately, these continuous fiber composites exhibit flaws and dry spots due to inadequate wetting of the fibers, which results in poor durability and strength in the formed products. Another problem with such continuous fiber composites is that the thermoplastic resins utilized often cannot withstand high temperature processing and/or applications.
In an attempt to alleviate such problems, polyarylene sulfides have been examined as a thermoplastic matrix for use in forming continuous fiber composites. Polyarylene sulfides are high-performance polymers that may withstand high thermal, chemical, and mechanical stresses and are beneficially utilized in a wide variety of applications. A significant problem with polyarylene sulfide-based continuous fiber composites however is that they typically suffer from poor consolidation due to poor adhesion between the polyarylene sulfide polymer and the continuous fiber, particularly when utilizing continuous carbon fibers. Use of high molecular weight polyarylene sulfides has shown promise in forming continuous fiber composites as the high molecular weight polyarylene sulfide is understood to have better adhesion with the continuous fiber due to higher levels of intermolecular chain entanglement. Unfortunately, high molecular weight polyarylene sulfides have high melt viscosity, and this presents processibility issues that may complicate formation techniques. In response, loading levels of continuous fibers in the composites have been limited so as to balance processibility of the materials with desired mechanical properties of the formed continuous fiber composites.
A need currently exists for a continuous fiber composite that is formed from a polyarylene sulfide polymer and includes a high continuous fiber loading level. Useful composites will be capable of achieving the desired strength, durability, and temperature performance demanded by desired applications while exhibiting good processibility characteristics during formation.